CDK4 and breast cancer: Remarkable progress in the survival rates of HR‐positive and HER2‐positive breast cancers has been made possible by the development of cutting‐edge treatments, such as monoclonal antibodies targeting HER2, Antibody‐drug conjugates, and inhibitors of cyclin‐dependent kinase 4/6 (CDK4/6) (Martin et al.2022; von Minckwitz et al.2019).